If you're back in the office this week be careful what you post on social media because sometimes you just don't know who your friends (or followers) really are.

Fair Work Commissioner, Leigh Johns warned on Monday that every year Australian workers find their employment in terminal strife over comments made on platforms like Twitter and Facebook.

While talking about work online is always risky; being gainfully employed doesn't necessarily mean you need to disengage from the online community altogether.

Anthony Mason is a social media expert at SR7 which advises individuals and organisations on how to stay out of trouble online.

Chatting with Jen Fleming on 702 ABC Sydney Breakfast Anthony explained that it's possible to stay off the Boss's feed and out their office as long as you think before you post.

"It's not all just venting or writing that you're bored at work or unhappy. People need to be considering a wide range of the kind of comment and commentary that's just not acceptable online."

And privacy settings are no safeguard against errant online comments being seen by the wrong people. While some social media platforms do allow you to restrict who has access to what you post this doesn't always mean your carefully worded thoughts about having to work on the Australia Day public holiday won't end up in front of the boss eventually.

Anthony's advice: treat everything you post as if it is public.

"It's not only about being wise about what you're posting on social media but, about being really quiet aware of just how public some of the comments really are."

"It's unreasonable now in 2014 to believe that some of your social media networks are fully private."

"You're playing with fire if you're living under the belief that you're immune and it's your best of friends that are viewing this content."